A place like the Right Livers' Rest was bound to draw freaks, same as molasses draws flies. 1935, George Goodchild, chapter 5, in Death on the Centre Court: By one o'clock the place was choc-a-bloc.
Swallowing certain types of poisons may cause excessive salivation. According to the National Library of Medicine, pesticides can cause excessive saliva when they are swallowed. Venom from snake bites or insect stings is another type of poisoning that can cause the malady.
However excessive drooling caused by too much saliva in the mouth is not normal and can be a sign of a serious condition. There are a number of different causes for ptylism or excessive saliva production in dogs. Some can be local issues in the mouth or throat, while others are more systemic disorders.